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In thermodynamics and chemical engineering, the vapor–liquid equilibrium (VLE) describes the distribution of a chemical species between the vapor phase and a liquid phase. The concentration of a vapor in contact with its liquid, especially at equilibrium , is often expressed in terms of vapor pressure , which will be a partial pressure (a ...
A Kugelrohr (German for "ball tube") is a short-path vacuum distillation apparatus [1]: 150 typically used to distill relatively small amounts of compounds with high boiling points (usually greater than 300 °C) under greatly reduced pressure.
A rotary evaporator [1] (rotovap) is a device used in chemical laboratories for the efficient and gentle removal of solvents from samples by evaporation.When referenced in the chemistry research literature, description of the use of this technique and equipment may include the phrase "rotary evaporator", though use is often rather signaled by other language (e.g., "the sample was evaporated ...
The equilibrium vapor pressure is an indication of a liquid's thermodynamic tendency to evaporate. It relates to the balance of particles escaping from the liquid (or solid) in equilibrium with those in a coexisting vapor phase. A substance with a high vapor pressure at normal temperatures is often referred to as volatile. The pressure ...
Vapor–liquid equilibrium(VLE): Vapor–liquid K values, relative volatilities, ideal and non-ideal systems, phase diagrams, calculating bubble points and dew points; Key fractional distillation concepts: theoretical stages, x-y diagrams, multicomponent distillation, column composition and temperature profiles
Cloth, treated to be hydrophobic, shows a high contact angle. The theoretical description of contact angle arises from the consideration of a thermodynamic equilibrium between the three phases: the liquid phase (L), the solid phase (S), and the gas or vapor phase (G) (which could be a mixture of ambient atmosphere and an equilibrium concentration of the liquid vapor).
The apparatus shown in the diagram represents a batch distillation as opposed to a continuous distillation. The liquid feed mixture to be distilled is placed into the round-bottomed flask along with a few anti-bumping granules, and the fractionating column is fitted into the top. As the mixture is heated and boils, vapor rises up the column.
In that case the phase rule implies that the equilibrium temperature (boiling point) and vapour-phase composition are determined. Liquid–vapour phase diagrams for other systems may have azeotropes (maxima or minima) in the composition curves, but the application of the phase rule is unchanged. The only difference is that the compositions of ...